1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * The Mach Operating System project at Carnegie-Mellon University. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * from: @(#)vm_object.c 8.5 (Berkeley) 3/22/94 33 * 34 * 35 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 36 * All rights reserved. 37 * 38 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 39 * 40 * Permission to use, copy, modify and distribute this software and 41 * its documentation is hereby granted, provided that both the copyright 42 * notice and this permission notice appear in all copies of the 43 * software, derivative works or modified versions, and any portions 44 * thereof, and that both notices appear in supporting documentation. 45 * 46 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 47 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 48 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 49 * 50 * Carnegie Mellon requests users of this software to return to 51 * 52 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 53 * School of Computer Science 54 * Carnegie Mellon University 55 * Pittsburgh PA 15213-3890 56 * 57 * any improvements or extensions that they make and grant Carnegie the 58 * rights to redistribute these changes. 59 */ 60 61 /* 62 * Virtual memory object module. 63 */ 64 65 #include <sys/cdefs.h> 66 __FBSDID("$FreeBSD$"); 67 68 #include <sys/param.h> 69 #include <sys/systm.h> 70 #include <sys/lock.h> 71 #include <sys/mman.h> 72 #include <sys/mount.h> 73 #include <sys/kernel.h> 74 #include <sys/sysctl.h> 75 #include <sys/mutex.h> 76 #include <sys/proc.h> /* for curproc, pageproc */ 77 #include <sys/socket.h> 78 #include <sys/vnode.h> 79 #include <sys/vmmeter.h> 80 #include <sys/sx.h> 81 82 #include <vm/vm.h> 83 #include <vm/vm_param.h> 84 #include <vm/pmap.h> 85 #include <vm/vm_map.h> 86 #include <vm/vm_object.h> 87 #include <vm/vm_page.h> 88 #include <vm/vm_pageout.h> 89 #include <vm/vm_pager.h> 90 #include <vm/swap_pager.h> 91 #include <vm/vm_kern.h> 92 #include <vm/vm_extern.h> 93 #include <vm/uma.h> 94 95 #define EASY_SCAN_FACTOR 8 96 97 #define MSYNC_FLUSH_HARDSEQ 0x01 98 #define MSYNC_FLUSH_SOFTSEQ 0x02 99 100 /* 101 * msync / VM object flushing optimizations 102 */ 103 static int msync_flush_flags = MSYNC_FLUSH_HARDSEQ | MSYNC_FLUSH_SOFTSEQ; 104 SYSCTL_INT(_vm, OID_AUTO, msync_flush_flags, 105 CTLFLAG_RW, &msync_flush_flags, 0, ""); 106 107 static int old_msync; 108 SYSCTL_INT(_vm, OID_AUTO, old_msync, CTLFLAG_RW, &old_msync, 0, 109 "Use old (insecure) msync behavior"); 110 111 static void vm_object_qcollapse(vm_object_t object); 112 static int vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags); 113 static void vm_object_vndeallocate(vm_object_t object); 114 115 /* 116 * Virtual memory objects maintain the actual data 117 * associated with allocated virtual memory. A given 118 * page of memory exists within exactly one object. 119 * 120 * An object is only deallocated when all "references" 121 * are given up. Only one "reference" to a given 122 * region of an object should be writeable. 123 * 124 * Associated with each object is a list of all resident 125 * memory pages belonging to that object; this list is 126 * maintained by the "vm_page" module, and locked by the object's 127 * lock. 128 * 129 * Each object also records a "pager" routine which is 130 * used to retrieve (and store) pages to the proper backing 131 * storage. In addition, objects may be backed by other 132 * objects from which they were virtual-copied. 133 * 134 * The only items within the object structure which are 135 * modified after time of creation are: 136 * reference count locked by object's lock 137 * pager routine locked by object's lock 138 * 139 */ 140 141 struct object_q vm_object_list; 142 struct mtx vm_object_list_mtx; /* lock for object list and count */ 143 144 struct vm_object kernel_object_store; 145 struct vm_object kmem_object_store; 146 147 SYSCTL_NODE(_vm_stats, OID_AUTO, object, CTLFLAG_RD, 0, "VM object stats"); 148 149 static long object_collapses; 150 SYSCTL_LONG(_vm_stats_object, OID_AUTO, collapses, CTLFLAG_RD, 151 &object_collapses, 0, "VM object collapses"); 152 153 static long object_bypasses; 154 SYSCTL_LONG(_vm_stats_object, OID_AUTO, bypasses, CTLFLAG_RD, 155 &object_bypasses, 0, "VM object bypasses"); 156 157 static uma_zone_t obj_zone; 158 159 static int vm_object_zinit(void *mem, int size, int flags); 160 161 #ifdef INVARIANTS 162 static void vm_object_zdtor(void *mem, int size, void *arg); 163 164 static void 165 vm_object_zdtor(void *mem, int size, void *arg) 166 { 167 vm_object_t object; 168 169 object = (vm_object_t)mem; 170 KASSERT(TAILQ_EMPTY(&object->memq), 171 ("object %p has resident pages", 172 object)); 173 KASSERT(object->paging_in_progress == 0, 174 ("object %p paging_in_progress = %d", 175 object, object->paging_in_progress)); 176 KASSERT(object->resident_page_count == 0, 177 ("object %p resident_page_count = %d", 178 object, object->resident_page_count)); 179 KASSERT(object->shadow_count == 0, 180 ("object %p shadow_count = %d", 181 object, object->shadow_count)); 182 } 183 #endif 184 185 static int 186 vm_object_zinit(void *mem, int size, int flags) 187 { 188 vm_object_t object; 189 190 object = (vm_object_t)mem; 191 bzero(&object->mtx, sizeof(object->mtx)); 192 VM_OBJECT_LOCK_INIT(object, "standard object"); 193 194 /* These are true for any object that has been freed */ 195 object->paging_in_progress = 0; 196 object->resident_page_count = 0; 197 object->shadow_count = 0; 198 return (0); 199 } 200 201 void 202 _vm_object_allocate(objtype_t type, vm_pindex_t size, vm_object_t object) 203 { 204 205 TAILQ_INIT(&object->memq); 206 LIST_INIT(&object->shadow_head); 207 208 object->root = NULL; 209 object->type = type; 210 object->size = size; 211 object->generation = 1; 212 object->ref_count = 1; 213 object->flags = 0; 214 if ((object->type == OBJT_DEFAULT) || (object->type == OBJT_SWAP)) 215 object->flags = OBJ_ONEMAPPING; 216 object->pg_color = 0; 217 object->handle = NULL; 218 object->backing_object = NULL; 219 object->backing_object_offset = (vm_ooffset_t) 0; 220 221 mtx_lock(&vm_object_list_mtx); 222 TAILQ_INSERT_TAIL(&vm_object_list, object, object_list); 223 mtx_unlock(&vm_object_list_mtx); 224 } 225 226 /* 227 * vm_object_init: 228 * 229 * Initialize the VM objects module. 230 */ 231 void 232 vm_object_init(void) 233 { 234 TAILQ_INIT(&vm_object_list); 235 mtx_init(&vm_object_list_mtx, "vm object_list", NULL, MTX_DEF); 236 237 VM_OBJECT_LOCK_INIT(&kernel_object_store, "kernel object"); 238 _vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 239 kernel_object); 240 241 VM_OBJECT_LOCK_INIT(&kmem_object_store, "kmem object"); 242 _vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 243 kmem_object); 244 245 /* 246 * The lock portion of struct vm_object must be type stable due 247 * to vm_pageout_fallback_object_lock locking a vm object 248 * without holding any references to it. 249 */ 250 obj_zone = uma_zcreate("VM OBJECT", sizeof (struct vm_object), NULL, 251 #ifdef INVARIANTS 252 vm_object_zdtor, 253 #else 254 NULL, 255 #endif 256 vm_object_zinit, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM|UMA_ZONE_NOFREE); 257 } 258 259 void 260 vm_object_clear_flag(vm_object_t object, u_short bits) 261 { 262 263 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 264 object->flags &= ~bits; 265 } 266 267 void 268 vm_object_pip_add(vm_object_t object, short i) 269 { 270 271 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 272 object->paging_in_progress += i; 273 } 274 275 void 276 vm_object_pip_subtract(vm_object_t object, short i) 277 { 278 279 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 280 object->paging_in_progress -= i; 281 } 282 283 void 284 vm_object_pip_wakeup(vm_object_t object) 285 { 286 287 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 288 object->paging_in_progress--; 289 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 290 vm_object_clear_flag(object, OBJ_PIPWNT); 291 wakeup(object); 292 } 293 } 294 295 void 296 vm_object_pip_wakeupn(vm_object_t object, short i) 297 { 298 299 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 300 if (i) 301 object->paging_in_progress -= i; 302 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 303 vm_object_clear_flag(object, OBJ_PIPWNT); 304 wakeup(object); 305 } 306 } 307 308 void 309 vm_object_pip_wait(vm_object_t object, char *waitid) 310 { 311 312 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 313 while (object->paging_in_progress) { 314 object->flags |= OBJ_PIPWNT; 315 msleep(object, VM_OBJECT_MTX(object), PVM, waitid, 0); 316 } 317 } 318 319 /* 320 * vm_object_allocate: 321 * 322 * Returns a new object with the given size. 323 */ 324 vm_object_t 325 vm_object_allocate(objtype_t type, vm_pindex_t size) 326 { 327 vm_object_t object; 328 329 object = (vm_object_t)uma_zalloc(obj_zone, M_WAITOK); 330 _vm_object_allocate(type, size, object); 331 return (object); 332 } 333 334 335 /* 336 * vm_object_reference: 337 * 338 * Gets another reference to the given object. Note: OBJ_DEAD 339 * objects can be referenced during final cleaning. 340 */ 341 void 342 vm_object_reference(vm_object_t object) 343 { 344 struct vnode *vp; 345 346 if (object == NULL) 347 return; 348 VM_OBJECT_LOCK(object); 349 object->ref_count++; 350 if (object->type == OBJT_VNODE) { 351 int vfslocked; 352 353 vp = object->handle; 354 VM_OBJECT_UNLOCK(object); 355 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 356 vget(vp, LK_RETRY, curthread); 357 VFS_UNLOCK_GIANT(vfslocked); 358 } else 359 VM_OBJECT_UNLOCK(object); 360 } 361 362 /* 363 * vm_object_reference_locked: 364 * 365 * Gets another reference to the given object. 366 * 367 * The object must be locked. 368 */ 369 void 370 vm_object_reference_locked(vm_object_t object) 371 { 372 struct vnode *vp; 373 374 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 375 KASSERT((object->flags & OBJ_DEAD) == 0, 376 ("vm_object_reference_locked: dead object referenced")); 377 object->ref_count++; 378 if (object->type == OBJT_VNODE) { 379 vp = object->handle; 380 vref(vp); 381 } 382 } 383 384 /* 385 * Handle deallocating an object of type OBJT_VNODE. 386 */ 387 static void 388 vm_object_vndeallocate(vm_object_t object) 389 { 390 struct vnode *vp = (struct vnode *) object->handle; 391 392 VFS_ASSERT_GIANT(vp->v_mount); 393 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 394 KASSERT(object->type == OBJT_VNODE, 395 ("vm_object_vndeallocate: not a vnode object")); 396 KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp")); 397 #ifdef INVARIANTS 398 if (object->ref_count == 0) { 399 vprint("vm_object_vndeallocate", vp); 400 panic("vm_object_vndeallocate: bad object reference count"); 401 } 402 #endif 403 404 object->ref_count--; 405 if (object->ref_count == 0) { 406 mp_fixme("Unlocked vflag access."); 407 vp->v_vflag &= ~VV_TEXT; 408 } 409 VM_OBJECT_UNLOCK(object); 410 /* 411 * vrele may need a vop lock 412 */ 413 vrele(vp); 414 } 415 416 /* 417 * vm_object_deallocate: 418 * 419 * Release a reference to the specified object, 420 * gained either through a vm_object_allocate 421 * or a vm_object_reference call. When all references 422 * are gone, storage associated with this object 423 * may be relinquished. 424 * 425 * No object may be locked. 426 */ 427 void 428 vm_object_deallocate(vm_object_t object) 429 { 430 vm_object_t temp; 431 432 while (object != NULL) { 433 int vfslocked; 434 435 vfslocked = 0; 436 restart: 437 VM_OBJECT_LOCK(object); 438 if (object->type == OBJT_VNODE) { 439 struct vnode *vp = (struct vnode *) object->handle; 440 441 /* 442 * Conditionally acquire Giant for a vnode-backed 443 * object. We have to be careful since the type of 444 * a vnode object can change while the object is 445 * unlocked. 446 */ 447 if (VFS_NEEDSGIANT(vp->v_mount) && !vfslocked) { 448 vfslocked = 1; 449 if (!mtx_trylock(&Giant)) { 450 VM_OBJECT_UNLOCK(object); 451 mtx_lock(&Giant); 452 goto restart; 453 } 454 } 455 vm_object_vndeallocate(object); 456 VFS_UNLOCK_GIANT(vfslocked); 457 return; 458 } else 459 /* 460 * This is to handle the case that the object 461 * changed type while we dropped its lock to 462 * obtain Giant. 463 */ 464 VFS_UNLOCK_GIANT(vfslocked); 465 466 KASSERT(object->ref_count != 0, 467 ("vm_object_deallocate: object deallocated too many times: %d", object->type)); 468 469 /* 470 * If the reference count goes to 0 we start calling 471 * vm_object_terminate() on the object chain. 472 * A ref count of 1 may be a special case depending on the 473 * shadow count being 0 or 1. 474 */ 475 object->ref_count--; 476 if (object->ref_count > 1) { 477 VM_OBJECT_UNLOCK(object); 478 return; 479 } else if (object->ref_count == 1) { 480 if (object->shadow_count == 0) { 481 vm_object_set_flag(object, OBJ_ONEMAPPING); 482 } else if ((object->shadow_count == 1) && 483 (object->handle == NULL) && 484 (object->type == OBJT_DEFAULT || 485 object->type == OBJT_SWAP)) { 486 vm_object_t robject; 487 488 robject = LIST_FIRST(&object->shadow_head); 489 KASSERT(robject != NULL, 490 ("vm_object_deallocate: ref_count: %d, shadow_count: %d", 491 object->ref_count, 492 object->shadow_count)); 493 if (!VM_OBJECT_TRYLOCK(robject)) { 494 /* 495 * Avoid a potential deadlock. 496 */ 497 object->ref_count++; 498 VM_OBJECT_UNLOCK(object); 499 /* 500 * More likely than not the thread 501 * holding robject's lock has lower 502 * priority than the current thread. 503 * Let the lower priority thread run. 504 */ 505 pause("vmo_de", 1); 506 continue; 507 } 508 /* 509 * Collapse object into its shadow unless its 510 * shadow is dead. In that case, object will 511 * be deallocated by the thread that is 512 * deallocating its shadow. 513 */ 514 if ((robject->flags & OBJ_DEAD) == 0 && 515 (robject->handle == NULL) && 516 (robject->type == OBJT_DEFAULT || 517 robject->type == OBJT_SWAP)) { 518 519 robject->ref_count++; 520 retry: 521 if (robject->paging_in_progress) { 522 VM_OBJECT_UNLOCK(object); 523 vm_object_pip_wait(robject, 524 "objde1"); 525 temp = robject->backing_object; 526 if (object == temp) { 527 VM_OBJECT_LOCK(object); 528 goto retry; 529 } 530 } else if (object->paging_in_progress) { 531 VM_OBJECT_UNLOCK(robject); 532 object->flags |= OBJ_PIPWNT; 533 msleep(object, 534 VM_OBJECT_MTX(object), 535 PDROP | PVM, "objde2", 0); 536 VM_OBJECT_LOCK(robject); 537 temp = robject->backing_object; 538 if (object == temp) { 539 VM_OBJECT_LOCK(object); 540 goto retry; 541 } 542 } else 543 VM_OBJECT_UNLOCK(object); 544 545 if (robject->ref_count == 1) { 546 robject->ref_count--; 547 object = robject; 548 goto doterm; 549 } 550 object = robject; 551 vm_object_collapse(object); 552 VM_OBJECT_UNLOCK(object); 553 continue; 554 } 555 VM_OBJECT_UNLOCK(robject); 556 } 557 VM_OBJECT_UNLOCK(object); 558 return; 559 } 560 doterm: 561 temp = object->backing_object; 562 if (temp != NULL) { 563 VM_OBJECT_LOCK(temp); 564 LIST_REMOVE(object, shadow_list); 565 temp->shadow_count--; 566 temp->generation++; 567 VM_OBJECT_UNLOCK(temp); 568 object->backing_object = NULL; 569 } 570 /* 571 * Don't double-terminate, we could be in a termination 572 * recursion due to the terminate having to sync data 573 * to disk. 574 */ 575 if ((object->flags & OBJ_DEAD) == 0) 576 vm_object_terminate(object); 577 else 578 VM_OBJECT_UNLOCK(object); 579 object = temp; 580 } 581 } 582 583 /* 584 * vm_object_terminate actually destroys the specified object, freeing 585 * up all previously used resources. 586 * 587 * The object must be locked. 588 * This routine may block. 589 */ 590 void 591 vm_object_terminate(vm_object_t object) 592 { 593 vm_page_t p; 594 595 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 596 597 /* 598 * Make sure no one uses us. 599 */ 600 vm_object_set_flag(object, OBJ_DEAD); 601 602 /* 603 * wait for the pageout daemon to be done with the object 604 */ 605 vm_object_pip_wait(object, "objtrm"); 606 607 KASSERT(!object->paging_in_progress, 608 ("vm_object_terminate: pageout in progress")); 609 610 /* 611 * Clean and free the pages, as appropriate. All references to the 612 * object are gone, so we don't need to lock it. 613 */ 614 if (object->type == OBJT_VNODE) { 615 struct vnode *vp = (struct vnode *)object->handle; 616 617 /* 618 * Clean pages and flush buffers. 619 */ 620 vm_object_page_clean(object, 0, 0, OBJPC_SYNC); 621 VM_OBJECT_UNLOCK(object); 622 623 vinvalbuf(vp, V_SAVE, NULL, 0, 0); 624 625 VM_OBJECT_LOCK(object); 626 } 627 628 KASSERT(object->ref_count == 0, 629 ("vm_object_terminate: object with references, ref_count=%d", 630 object->ref_count)); 631 632 /* 633 * Now free any remaining pages. For internal objects, this also 634 * removes them from paging queues. Don't free wired pages, just 635 * remove them from the object. 636 */ 637 vm_page_lock_queues(); 638 while ((p = TAILQ_FIRST(&object->memq)) != NULL) { 639 KASSERT(!p->busy && (p->oflags & VPO_BUSY) == 0, 640 ("vm_object_terminate: freeing busy page %p " 641 "p->busy = %d, p->flags %x\n", p, p->busy, p->flags)); 642 if (p->wire_count == 0) { 643 vm_page_free(p); 644 cnt.v_pfree++; 645 } else { 646 vm_page_remove(p); 647 } 648 } 649 vm_page_unlock_queues(); 650 651 /* 652 * Let the pager know object is dead. 653 */ 654 vm_pager_deallocate(object); 655 VM_OBJECT_UNLOCK(object); 656 657 /* 658 * Remove the object from the global object list. 659 */ 660 mtx_lock(&vm_object_list_mtx); 661 TAILQ_REMOVE(&vm_object_list, object, object_list); 662 mtx_unlock(&vm_object_list_mtx); 663 664 /* 665 * Free the space for the object. 666 */ 667 uma_zfree(obj_zone, object); 668 } 669 670 /* 671 * vm_object_page_clean 672 * 673 * Clean all dirty pages in the specified range of object. Leaves page 674 * on whatever queue it is currently on. If NOSYNC is set then do not 675 * write out pages with VPO_NOSYNC set (originally comes from MAP_NOSYNC), 676 * leaving the object dirty. 677 * 678 * When stuffing pages asynchronously, allow clustering. XXX we need a 679 * synchronous clustering mode implementation. 680 * 681 * Odd semantics: if start == end, we clean everything. 682 * 683 * The object must be locked. 684 */ 685 void 686 vm_object_page_clean(vm_object_t object, vm_pindex_t start, vm_pindex_t end, int flags) 687 { 688 vm_page_t p, np; 689 vm_pindex_t tstart, tend; 690 vm_pindex_t pi; 691 int clearobjflags; 692 int pagerflags; 693 int curgeneration; 694 695 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 696 if (object->type != OBJT_VNODE || 697 (object->flags & OBJ_MIGHTBEDIRTY) == 0) 698 return; 699 700 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) ? VM_PAGER_PUT_SYNC : VM_PAGER_CLUSTER_OK; 701 pagerflags |= (flags & OBJPC_INVAL) ? VM_PAGER_PUT_INVAL : 0; 702 703 vm_object_set_flag(object, OBJ_CLEANING); 704 705 tstart = start; 706 if (end == 0) { 707 tend = object->size; 708 } else { 709 tend = end; 710 } 711 712 vm_page_lock_queues(); 713 /* 714 * If the caller is smart and only msync()s a range he knows is 715 * dirty, we may be able to avoid an object scan. This results in 716 * a phenominal improvement in performance. We cannot do this 717 * as a matter of course because the object may be huge - e.g. 718 * the size might be in the gigabytes or terrabytes. 719 */ 720 if (msync_flush_flags & MSYNC_FLUSH_HARDSEQ) { 721 vm_pindex_t tscan; 722 int scanlimit; 723 int scanreset; 724 725 scanreset = object->resident_page_count / EASY_SCAN_FACTOR; 726 if (scanreset < 16) 727 scanreset = 16; 728 pagerflags |= VM_PAGER_IGNORE_CLEANCHK; 729 730 scanlimit = scanreset; 731 tscan = tstart; 732 while (tscan < tend) { 733 curgeneration = object->generation; 734 p = vm_page_lookup(object, tscan); 735 if (p == NULL || p->valid == 0 || 736 VM_PAGE_INQUEUE1(p, PQ_CACHE)) { 737 if (--scanlimit == 0) 738 break; 739 ++tscan; 740 continue; 741 } 742 vm_page_test_dirty(p); 743 if ((p->dirty & p->valid) == 0) { 744 if (--scanlimit == 0) 745 break; 746 ++tscan; 747 continue; 748 } 749 /* 750 * If we have been asked to skip nosync pages and 751 * this is a nosync page, we can't continue. 752 */ 753 if ((flags & OBJPC_NOSYNC) && (p->oflags & VPO_NOSYNC)) { 754 if (--scanlimit == 0) 755 break; 756 ++tscan; 757 continue; 758 } 759 scanlimit = scanreset; 760 761 /* 762 * This returns 0 if it was unable to busy the first 763 * page (i.e. had to sleep). 764 */ 765 tscan += vm_object_page_collect_flush(object, p, curgeneration, pagerflags); 766 } 767 768 /* 769 * If everything was dirty and we flushed it successfully, 770 * and the requested range is not the entire object, we 771 * don't have to mess with CLEANCHK or MIGHTBEDIRTY and can 772 * return immediately. 773 */ 774 if (tscan >= tend && (tstart || tend < object->size)) { 775 vm_page_unlock_queues(); 776 vm_object_clear_flag(object, OBJ_CLEANING); 777 return; 778 } 779 pagerflags &= ~VM_PAGER_IGNORE_CLEANCHK; 780 } 781 782 /* 783 * Generally set CLEANCHK interlock and make the page read-only so 784 * we can then clear the object flags. 785 * 786 * However, if this is a nosync mmap then the object is likely to 787 * stay dirty so do not mess with the page and do not clear the 788 * object flags. 789 */ 790 clearobjflags = 1; 791 TAILQ_FOREACH(p, &object->memq, listq) { 792 p->oflags |= VPO_CLEANCHK; 793 if ((flags & OBJPC_NOSYNC) && (p->oflags & VPO_NOSYNC)) 794 clearobjflags = 0; 795 else 796 pmap_remove_write(p); 797 } 798 799 if (clearobjflags && (tstart == 0) && (tend == object->size)) { 800 struct vnode *vp; 801 802 vm_object_clear_flag(object, OBJ_MIGHTBEDIRTY); 803 if (object->type == OBJT_VNODE && 804 (vp = (struct vnode *)object->handle) != NULL) { 805 VI_LOCK(vp); 806 if (vp->v_iflag & VI_OBJDIRTY) 807 vp->v_iflag &= ~VI_OBJDIRTY; 808 VI_UNLOCK(vp); 809 } 810 } 811 812 rescan: 813 curgeneration = object->generation; 814 815 for (p = TAILQ_FIRST(&object->memq); p; p = np) { 816 int n; 817 818 np = TAILQ_NEXT(p, listq); 819 820 again: 821 pi = p->pindex; 822 if ((p->oflags & VPO_CLEANCHK) == 0 || 823 (pi < tstart) || (pi >= tend) || 824 (p->valid == 0) || 825 VM_PAGE_INQUEUE1(p, PQ_CACHE)) { 826 p->oflags &= ~VPO_CLEANCHK; 827 continue; 828 } 829 830 vm_page_test_dirty(p); 831 if ((p->dirty & p->valid) == 0) { 832 p->oflags &= ~VPO_CLEANCHK; 833 continue; 834 } 835 836 /* 837 * If we have been asked to skip nosync pages and this is a 838 * nosync page, skip it. Note that the object flags were 839 * not cleared in this case so we do not have to set them. 840 */ 841 if ((flags & OBJPC_NOSYNC) && (p->oflags & VPO_NOSYNC)) { 842 p->oflags &= ~VPO_CLEANCHK; 843 continue; 844 } 845 846 n = vm_object_page_collect_flush(object, p, 847 curgeneration, pagerflags); 848 if (n == 0) 849 goto rescan; 850 851 if (object->generation != curgeneration) 852 goto rescan; 853 854 /* 855 * Try to optimize the next page. If we can't we pick up 856 * our (random) scan where we left off. 857 */ 858 if (msync_flush_flags & MSYNC_FLUSH_SOFTSEQ) { 859 if ((p = vm_page_lookup(object, pi + n)) != NULL) 860 goto again; 861 } 862 } 863 vm_page_unlock_queues(); 864 #if 0 865 VOP_FSYNC(vp, (pagerflags & VM_PAGER_PUT_SYNC)?MNT_WAIT:0, curproc); 866 #endif 867 868 vm_object_clear_flag(object, OBJ_CLEANING); 869 return; 870 } 871 872 static int 873 vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags) 874 { 875 int runlen; 876 int maxf; 877 int chkb; 878 int maxb; 879 int i; 880 vm_pindex_t pi; 881 vm_page_t maf[vm_pageout_page_count]; 882 vm_page_t mab[vm_pageout_page_count]; 883 vm_page_t ma[vm_pageout_page_count]; 884 885 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 886 pi = p->pindex; 887 while (vm_page_sleep_if_busy(p, TRUE, "vpcwai")) { 888 vm_page_lock_queues(); 889 if (object->generation != curgeneration) { 890 return(0); 891 } 892 } 893 maxf = 0; 894 for(i = 1; i < vm_pageout_page_count; i++) { 895 vm_page_t tp; 896 897 if ((tp = vm_page_lookup(object, pi + i)) != NULL) { 898 if ((tp->oflags & VPO_BUSY) || 899 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 900 (tp->oflags & VPO_CLEANCHK) == 0) || 901 (tp->busy != 0)) 902 break; 903 if (VM_PAGE_INQUEUE1(tp, PQ_CACHE)) { 904 tp->oflags &= ~VPO_CLEANCHK; 905 break; 906 } 907 vm_page_test_dirty(tp); 908 if ((tp->dirty & tp->valid) == 0) { 909 tp->oflags &= ~VPO_CLEANCHK; 910 break; 911 } 912 maf[ i - 1 ] = tp; 913 maxf++; 914 continue; 915 } 916 break; 917 } 918 919 maxb = 0; 920 chkb = vm_pageout_page_count - maxf; 921 if (chkb) { 922 for(i = 1; i < chkb;i++) { 923 vm_page_t tp; 924 925 if ((tp = vm_page_lookup(object, pi - i)) != NULL) { 926 if ((tp->oflags & VPO_BUSY) || 927 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 928 (tp->oflags & VPO_CLEANCHK) == 0) || 929 (tp->busy != 0)) 930 break; 931 if (VM_PAGE_INQUEUE1(tp, PQ_CACHE)) { 932 tp->oflags &= ~VPO_CLEANCHK; 933 break; 934 } 935 vm_page_test_dirty(tp); 936 if ((tp->dirty & tp->valid) == 0) { 937 tp->oflags &= ~VPO_CLEANCHK; 938 break; 939 } 940 mab[ i - 1 ] = tp; 941 maxb++; 942 continue; 943 } 944 break; 945 } 946 } 947 948 for(i = 0; i < maxb; i++) { 949 int index = (maxb - i) - 1; 950 ma[index] = mab[i]; 951 ma[index]->oflags &= ~VPO_CLEANCHK; 952 } 953 p->oflags &= ~VPO_CLEANCHK; 954 ma[maxb] = p; 955 for(i = 0; i < maxf; i++) { 956 int index = (maxb + i) + 1; 957 ma[index] = maf[i]; 958 ma[index]->oflags &= ~VPO_CLEANCHK; 959 } 960 runlen = maxb + maxf + 1; 961 962 vm_pageout_flush(ma, runlen, pagerflags); 963 for (i = 0; i < runlen; i++) { 964 if (ma[i]->valid & ma[i]->dirty) { 965 pmap_remove_write(ma[i]); 966 ma[i]->oflags |= VPO_CLEANCHK; 967 968 /* 969 * maxf will end up being the actual number of pages 970 * we wrote out contiguously, non-inclusive of the 971 * first page. We do not count look-behind pages. 972 */ 973 if (i >= maxb + 1 && (maxf > i - maxb - 1)) 974 maxf = i - maxb - 1; 975 } 976 } 977 return(maxf + 1); 978 } 979 980 /* 981 * Note that there is absolutely no sense in writing out 982 * anonymous objects, so we track down the vnode object 983 * to write out. 984 * We invalidate (remove) all pages from the address space 985 * for semantic correctness. 986 * 987 * Note: certain anonymous maps, such as MAP_NOSYNC maps, 988 * may start out with a NULL object. 989 */ 990 void 991 vm_object_sync(vm_object_t object, vm_ooffset_t offset, vm_size_t size, 992 boolean_t syncio, boolean_t invalidate) 993 { 994 vm_object_t backing_object; 995 struct vnode *vp; 996 struct mount *mp; 997 int flags; 998 999 if (object == NULL) 1000 return; 1001 VM_OBJECT_LOCK(object); 1002 while ((backing_object = object->backing_object) != NULL) { 1003 VM_OBJECT_LOCK(backing_object); 1004 offset += object->backing_object_offset; 1005 VM_OBJECT_UNLOCK(object); 1006 object = backing_object; 1007 if (object->size < OFF_TO_IDX(offset + size)) 1008 size = IDX_TO_OFF(object->size) - offset; 1009 } 1010 /* 1011 * Flush pages if writing is allowed, invalidate them 1012 * if invalidation requested. Pages undergoing I/O 1013 * will be ignored by vm_object_page_remove(). 1014 * 1015 * We cannot lock the vnode and then wait for paging 1016 * to complete without deadlocking against vm_fault. 1017 * Instead we simply call vm_object_page_remove() and 1018 * allow it to block internally on a page-by-page 1019 * basis when it encounters pages undergoing async 1020 * I/O. 1021 */ 1022 if (object->type == OBJT_VNODE && 1023 (object->flags & OBJ_MIGHTBEDIRTY) != 0) { 1024 int vfslocked; 1025 vp = object->handle; 1026 VM_OBJECT_UNLOCK(object); 1027 (void) vn_start_write(vp, &mp, V_WAIT); 1028 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 1029 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, curthread); 1030 flags = (syncio || invalidate) ? OBJPC_SYNC : 0; 1031 flags |= invalidate ? OBJPC_INVAL : 0; 1032 VM_OBJECT_LOCK(object); 1033 vm_object_page_clean(object, 1034 OFF_TO_IDX(offset), 1035 OFF_TO_IDX(offset + size + PAGE_MASK), 1036 flags); 1037 VM_OBJECT_UNLOCK(object); 1038 VOP_UNLOCK(vp, 0, curthread); 1039 VFS_UNLOCK_GIANT(vfslocked); 1040 vn_finished_write(mp); 1041 VM_OBJECT_LOCK(object); 1042 } 1043 if ((object->type == OBJT_VNODE || 1044 object->type == OBJT_DEVICE) && invalidate) { 1045 boolean_t purge; 1046 purge = old_msync || (object->type == OBJT_DEVICE); 1047 vm_object_page_remove(object, 1048 OFF_TO_IDX(offset), 1049 OFF_TO_IDX(offset + size + PAGE_MASK), 1050 purge ? FALSE : TRUE); 1051 } 1052 VM_OBJECT_UNLOCK(object); 1053 } 1054 1055 /* 1056 * vm_object_madvise: 1057 * 1058 * Implements the madvise function at the object/page level. 1059 * 1060 * MADV_WILLNEED (any object) 1061 * 1062 * Activate the specified pages if they are resident. 1063 * 1064 * MADV_DONTNEED (any object) 1065 * 1066 * Deactivate the specified pages if they are resident. 1067 * 1068 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects, 1069 * OBJ_ONEMAPPING only) 1070 * 1071 * Deactivate and clean the specified pages if they are 1072 * resident. This permits the process to reuse the pages 1073 * without faulting or the kernel to reclaim the pages 1074 * without I/O. 1075 */ 1076 void 1077 vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise) 1078 { 1079 vm_pindex_t end, tpindex; 1080 vm_object_t backing_object, tobject; 1081 vm_page_t m; 1082 1083 if (object == NULL) 1084 return; 1085 VM_OBJECT_LOCK(object); 1086 end = pindex + count; 1087 /* 1088 * Locate and adjust resident pages 1089 */ 1090 for (; pindex < end; pindex += 1) { 1091 relookup: 1092 tobject = object; 1093 tpindex = pindex; 1094 shadowlookup: 1095 /* 1096 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages 1097 * and those pages must be OBJ_ONEMAPPING. 1098 */ 1099 if (advise == MADV_FREE) { 1100 if ((tobject->type != OBJT_DEFAULT && 1101 tobject->type != OBJT_SWAP) || 1102 (tobject->flags & OBJ_ONEMAPPING) == 0) { 1103 goto unlock_tobject; 1104 } 1105 } 1106 m = vm_page_lookup(tobject, tpindex); 1107 if (m == NULL) { 1108 /* 1109 * There may be swap even if there is no backing page 1110 */ 1111 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1112 swap_pager_freespace(tobject, tpindex, 1); 1113 /* 1114 * next object 1115 */ 1116 backing_object = tobject->backing_object; 1117 if (backing_object == NULL) 1118 goto unlock_tobject; 1119 VM_OBJECT_LOCK(backing_object); 1120 tpindex += OFF_TO_IDX(tobject->backing_object_offset); 1121 if (tobject != object) 1122 VM_OBJECT_UNLOCK(tobject); 1123 tobject = backing_object; 1124 goto shadowlookup; 1125 } 1126 /* 1127 * If the page is busy or not in a normal active state, 1128 * we skip it. If the page is not managed there are no 1129 * page queues to mess with. Things can break if we mess 1130 * with pages in any of the below states. 1131 */ 1132 vm_page_lock_queues(); 1133 if (m->hold_count || 1134 m->wire_count || 1135 (m->flags & PG_UNMANAGED) || 1136 m->valid != VM_PAGE_BITS_ALL) { 1137 vm_page_unlock_queues(); 1138 goto unlock_tobject; 1139 } 1140 if ((m->oflags & VPO_BUSY) || m->busy) { 1141 vm_page_flag_set(m, PG_REFERENCED); 1142 vm_page_unlock_queues(); 1143 if (object != tobject) 1144 VM_OBJECT_UNLOCK(object); 1145 m->oflags |= VPO_WANTED; 1146 msleep(m, VM_OBJECT_MTX(tobject), PDROP | PVM, "madvpo", 0); 1147 VM_OBJECT_LOCK(object); 1148 goto relookup; 1149 } 1150 if (advise == MADV_WILLNEED) { 1151 vm_page_activate(m); 1152 } else if (advise == MADV_DONTNEED) { 1153 vm_page_dontneed(m); 1154 } else if (advise == MADV_FREE) { 1155 /* 1156 * Mark the page clean. This will allow the page 1157 * to be freed up by the system. However, such pages 1158 * are often reused quickly by malloc()/free() 1159 * so we do not do anything that would cause 1160 * a page fault if we can help it. 1161 * 1162 * Specifically, we do not try to actually free 1163 * the page now nor do we try to put it in the 1164 * cache (which would cause a page fault on reuse). 1165 * 1166 * But we do make the page is freeable as we 1167 * can without actually taking the step of unmapping 1168 * it. 1169 */ 1170 pmap_clear_modify(m); 1171 m->dirty = 0; 1172 m->act_count = 0; 1173 vm_page_dontneed(m); 1174 } 1175 vm_page_unlock_queues(); 1176 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1177 swap_pager_freespace(tobject, tpindex, 1); 1178 unlock_tobject: 1179 if (tobject != object) 1180 VM_OBJECT_UNLOCK(tobject); 1181 } 1182 VM_OBJECT_UNLOCK(object); 1183 } 1184 1185 /* 1186 * vm_object_shadow: 1187 * 1188 * Create a new object which is backed by the 1189 * specified existing object range. The source 1190 * object reference is deallocated. 1191 * 1192 * The new object and offset into that object 1193 * are returned in the source parameters. 1194 */ 1195 void 1196 vm_object_shadow( 1197 vm_object_t *object, /* IN/OUT */ 1198 vm_ooffset_t *offset, /* IN/OUT */ 1199 vm_size_t length) 1200 { 1201 vm_object_t source; 1202 vm_object_t result; 1203 1204 source = *object; 1205 1206 /* 1207 * Don't create the new object if the old object isn't shared. 1208 */ 1209 if (source != NULL) { 1210 VM_OBJECT_LOCK(source); 1211 if (source->ref_count == 1 && 1212 source->handle == NULL && 1213 (source->type == OBJT_DEFAULT || 1214 source->type == OBJT_SWAP)) { 1215 VM_OBJECT_UNLOCK(source); 1216 return; 1217 } 1218 VM_OBJECT_UNLOCK(source); 1219 } 1220 1221 /* 1222 * Allocate a new object with the given length. 1223 */ 1224 result = vm_object_allocate(OBJT_DEFAULT, length); 1225 1226 /* 1227 * The new object shadows the source object, adding a reference to it. 1228 * Our caller changes his reference to point to the new object, 1229 * removing a reference to the source object. Net result: no change 1230 * of reference count. 1231 * 1232 * Try to optimize the result object's page color when shadowing 1233 * in order to maintain page coloring consistency in the combined 1234 * shadowed object. 1235 */ 1236 result->backing_object = source; 1237 /* 1238 * Store the offset into the source object, and fix up the offset into 1239 * the new object. 1240 */ 1241 result->backing_object_offset = *offset; 1242 if (source != NULL) { 1243 VM_OBJECT_LOCK(source); 1244 LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list); 1245 source->shadow_count++; 1246 source->generation++; 1247 result->flags |= source->flags & OBJ_NEEDGIANT; 1248 VM_OBJECT_UNLOCK(source); 1249 } 1250 1251 1252 /* 1253 * Return the new things 1254 */ 1255 *offset = 0; 1256 *object = result; 1257 } 1258 1259 /* 1260 * vm_object_split: 1261 * 1262 * Split the pages in a map entry into a new object. This affords 1263 * easier removal of unused pages, and keeps object inheritance from 1264 * being a negative impact on memory usage. 1265 */ 1266 void 1267 vm_object_split(vm_map_entry_t entry) 1268 { 1269 vm_page_t m, m_next; 1270 vm_object_t orig_object, new_object, source; 1271 vm_pindex_t idx, offidxstart; 1272 vm_size_t size; 1273 1274 orig_object = entry->object.vm_object; 1275 if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP) 1276 return; 1277 if (orig_object->ref_count <= 1) 1278 return; 1279 VM_OBJECT_UNLOCK(orig_object); 1280 1281 offidxstart = OFF_TO_IDX(entry->offset); 1282 size = atop(entry->end - entry->start); 1283 1284 /* 1285 * If swap_pager_copy() is later called, it will convert new_object 1286 * into a swap object. 1287 */ 1288 new_object = vm_object_allocate(OBJT_DEFAULT, size); 1289 1290 /* 1291 * At this point, the new object is still private, so the order in 1292 * which the original and new objects are locked does not matter. 1293 */ 1294 VM_OBJECT_LOCK(new_object); 1295 VM_OBJECT_LOCK(orig_object); 1296 source = orig_object->backing_object; 1297 if (source != NULL) { 1298 VM_OBJECT_LOCK(source); 1299 if ((source->flags & OBJ_DEAD) != 0) { 1300 VM_OBJECT_UNLOCK(source); 1301 VM_OBJECT_UNLOCK(orig_object); 1302 VM_OBJECT_UNLOCK(new_object); 1303 vm_object_deallocate(new_object); 1304 VM_OBJECT_LOCK(orig_object); 1305 return; 1306 } 1307 LIST_INSERT_HEAD(&source->shadow_head, 1308 new_object, shadow_list); 1309 source->shadow_count++; 1310 source->generation++; 1311 vm_object_reference_locked(source); /* for new_object */ 1312 vm_object_clear_flag(source, OBJ_ONEMAPPING); 1313 VM_OBJECT_UNLOCK(source); 1314 new_object->backing_object_offset = 1315 orig_object->backing_object_offset + entry->offset; 1316 new_object->backing_object = source; 1317 } 1318 new_object->flags |= orig_object->flags & OBJ_NEEDGIANT; 1319 retry: 1320 if ((m = TAILQ_FIRST(&orig_object->memq)) != NULL) { 1321 if (m->pindex < offidxstart) { 1322 m = vm_page_splay(offidxstart, orig_object->root); 1323 if ((orig_object->root = m)->pindex < offidxstart) 1324 m = TAILQ_NEXT(m, listq); 1325 } 1326 } 1327 vm_page_lock_queues(); 1328 for (; m != NULL && (idx = m->pindex - offidxstart) < size; 1329 m = m_next) { 1330 m_next = TAILQ_NEXT(m, listq); 1331 1332 /* 1333 * We must wait for pending I/O to complete before we can 1334 * rename the page. 1335 * 1336 * We do not have to VM_PROT_NONE the page as mappings should 1337 * not be changed by this operation. 1338 */ 1339 if ((m->oflags & VPO_BUSY) || m->busy) { 1340 vm_page_flag_set(m, PG_REFERENCED); 1341 vm_page_unlock_queues(); 1342 VM_OBJECT_UNLOCK(new_object); 1343 m->oflags |= VPO_WANTED; 1344 msleep(m, VM_OBJECT_MTX(orig_object), PVM, "spltwt", 0); 1345 VM_OBJECT_LOCK(new_object); 1346 goto retry; 1347 } 1348 vm_page_rename(m, new_object, idx); 1349 /* page automatically made dirty by rename and cache handled */ 1350 vm_page_busy(m); 1351 } 1352 vm_page_unlock_queues(); 1353 if (orig_object->type == OBJT_SWAP) { 1354 /* 1355 * swap_pager_copy() can sleep, in which case the orig_object's 1356 * and new_object's locks are released and reacquired. 1357 */ 1358 swap_pager_copy(orig_object, new_object, offidxstart, 0); 1359 } 1360 VM_OBJECT_UNLOCK(orig_object); 1361 TAILQ_FOREACH(m, &new_object->memq, listq) 1362 vm_page_wakeup(m); 1363 VM_OBJECT_UNLOCK(new_object); 1364 entry->object.vm_object = new_object; 1365 entry->offset = 0LL; 1366 vm_object_deallocate(orig_object); 1367 VM_OBJECT_LOCK(new_object); 1368 } 1369 1370 #define OBSC_TEST_ALL_SHADOWED 0x0001 1371 #define OBSC_COLLAPSE_NOWAIT 0x0002 1372 #define OBSC_COLLAPSE_WAIT 0x0004 1373 1374 static int 1375 vm_object_backing_scan(vm_object_t object, int op) 1376 { 1377 int r = 1; 1378 vm_page_t p; 1379 vm_object_t backing_object; 1380 vm_pindex_t backing_offset_index; 1381 1382 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1383 VM_OBJECT_LOCK_ASSERT(object->backing_object, MA_OWNED); 1384 1385 backing_object = object->backing_object; 1386 backing_offset_index = OFF_TO_IDX(object->backing_object_offset); 1387 1388 /* 1389 * Initial conditions 1390 */ 1391 if (op & OBSC_TEST_ALL_SHADOWED) { 1392 /* 1393 * We do not want to have to test for the existence of 1394 * swap pages in the backing object. XXX but with the 1395 * new swapper this would be pretty easy to do. 1396 * 1397 * XXX what about anonymous MAP_SHARED memory that hasn't 1398 * been ZFOD faulted yet? If we do not test for this, the 1399 * shadow test may succeed! XXX 1400 */ 1401 if (backing_object->type != OBJT_DEFAULT) { 1402 return (0); 1403 } 1404 } 1405 if (op & OBSC_COLLAPSE_WAIT) { 1406 vm_object_set_flag(backing_object, OBJ_DEAD); 1407 } 1408 1409 /* 1410 * Our scan 1411 */ 1412 p = TAILQ_FIRST(&backing_object->memq); 1413 while (p) { 1414 vm_page_t next = TAILQ_NEXT(p, listq); 1415 vm_pindex_t new_pindex = p->pindex - backing_offset_index; 1416 1417 if (op & OBSC_TEST_ALL_SHADOWED) { 1418 vm_page_t pp; 1419 1420 /* 1421 * Ignore pages outside the parent object's range 1422 * and outside the parent object's mapping of the 1423 * backing object. 1424 * 1425 * note that we do not busy the backing object's 1426 * page. 1427 */ 1428 if ( 1429 p->pindex < backing_offset_index || 1430 new_pindex >= object->size 1431 ) { 1432 p = next; 1433 continue; 1434 } 1435 1436 /* 1437 * See if the parent has the page or if the parent's 1438 * object pager has the page. If the parent has the 1439 * page but the page is not valid, the parent's 1440 * object pager must have the page. 1441 * 1442 * If this fails, the parent does not completely shadow 1443 * the object and we might as well give up now. 1444 */ 1445 1446 pp = vm_page_lookup(object, new_pindex); 1447 if ( 1448 (pp == NULL || pp->valid == 0) && 1449 !vm_pager_has_page(object, new_pindex, NULL, NULL) 1450 ) { 1451 r = 0; 1452 break; 1453 } 1454 } 1455 1456 /* 1457 * Check for busy page 1458 */ 1459 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) { 1460 vm_page_t pp; 1461 1462 if (op & OBSC_COLLAPSE_NOWAIT) { 1463 if ((p->oflags & VPO_BUSY) || 1464 !p->valid || 1465 p->busy) { 1466 p = next; 1467 continue; 1468 } 1469 } else if (op & OBSC_COLLAPSE_WAIT) { 1470 if ((p->oflags & VPO_BUSY) || p->busy) { 1471 vm_page_lock_queues(); 1472 vm_page_flag_set(p, PG_REFERENCED); 1473 vm_page_unlock_queues(); 1474 VM_OBJECT_UNLOCK(object); 1475 p->oflags |= VPO_WANTED; 1476 msleep(p, VM_OBJECT_MTX(backing_object), 1477 PDROP | PVM, "vmocol", 0); 1478 VM_OBJECT_LOCK(object); 1479 VM_OBJECT_LOCK(backing_object); 1480 /* 1481 * If we slept, anything could have 1482 * happened. Since the object is 1483 * marked dead, the backing offset 1484 * should not have changed so we 1485 * just restart our scan. 1486 */ 1487 p = TAILQ_FIRST(&backing_object->memq); 1488 continue; 1489 } 1490 } 1491 1492 KASSERT( 1493 p->object == backing_object, 1494 ("vm_object_backing_scan: object mismatch") 1495 ); 1496 1497 /* 1498 * Destroy any associated swap 1499 */ 1500 if (backing_object->type == OBJT_SWAP) { 1501 swap_pager_freespace( 1502 backing_object, 1503 p->pindex, 1504 1 1505 ); 1506 } 1507 1508 if ( 1509 p->pindex < backing_offset_index || 1510 new_pindex >= object->size 1511 ) { 1512 /* 1513 * Page is out of the parent object's range, we 1514 * can simply destroy it. 1515 */ 1516 vm_page_lock_queues(); 1517 KASSERT(!pmap_page_is_mapped(p), 1518 ("freeing mapped page %p", p)); 1519 if (p->wire_count == 0) 1520 vm_page_free(p); 1521 else 1522 vm_page_remove(p); 1523 vm_page_unlock_queues(); 1524 p = next; 1525 continue; 1526 } 1527 1528 pp = vm_page_lookup(object, new_pindex); 1529 if ( 1530 pp != NULL || 1531 vm_pager_has_page(object, new_pindex, NULL, NULL) 1532 ) { 1533 /* 1534 * page already exists in parent OR swap exists 1535 * for this location in the parent. Destroy 1536 * the original page from the backing object. 1537 * 1538 * Leave the parent's page alone 1539 */ 1540 vm_page_lock_queues(); 1541 KASSERT(!pmap_page_is_mapped(p), 1542 ("freeing mapped page %p", p)); 1543 if (p->wire_count == 0) 1544 vm_page_free(p); 1545 else 1546 vm_page_remove(p); 1547 vm_page_unlock_queues(); 1548 p = next; 1549 continue; 1550 } 1551 1552 /* 1553 * Page does not exist in parent, rename the 1554 * page from the backing object to the main object. 1555 * 1556 * If the page was mapped to a process, it can remain 1557 * mapped through the rename. 1558 */ 1559 vm_page_lock_queues(); 1560 vm_page_rename(p, object, new_pindex); 1561 vm_page_unlock_queues(); 1562 /* page automatically made dirty by rename */ 1563 } 1564 p = next; 1565 } 1566 return (r); 1567 } 1568 1569 1570 /* 1571 * this version of collapse allows the operation to occur earlier and 1572 * when paging_in_progress is true for an object... This is not a complete 1573 * operation, but should plug 99.9% of the rest of the leaks. 1574 */ 1575 static void 1576 vm_object_qcollapse(vm_object_t object) 1577 { 1578 vm_object_t backing_object = object->backing_object; 1579 1580 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1581 VM_OBJECT_LOCK_ASSERT(backing_object, MA_OWNED); 1582 1583 if (backing_object->ref_count != 1) 1584 return; 1585 1586 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT); 1587 } 1588 1589 /* 1590 * vm_object_collapse: 1591 * 1592 * Collapse an object with the object backing it. 1593 * Pages in the backing object are moved into the 1594 * parent, and the backing object is deallocated. 1595 */ 1596 void 1597 vm_object_collapse(vm_object_t object) 1598 { 1599 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1600 1601 while (TRUE) { 1602 vm_object_t backing_object; 1603 1604 /* 1605 * Verify that the conditions are right for collapse: 1606 * 1607 * The object exists and the backing object exists. 1608 */ 1609 if ((backing_object = object->backing_object) == NULL) 1610 break; 1611 1612 /* 1613 * we check the backing object first, because it is most likely 1614 * not collapsable. 1615 */ 1616 VM_OBJECT_LOCK(backing_object); 1617 if (backing_object->handle != NULL || 1618 (backing_object->type != OBJT_DEFAULT && 1619 backing_object->type != OBJT_SWAP) || 1620 (backing_object->flags & OBJ_DEAD) || 1621 object->handle != NULL || 1622 (object->type != OBJT_DEFAULT && 1623 object->type != OBJT_SWAP) || 1624 (object->flags & OBJ_DEAD)) { 1625 VM_OBJECT_UNLOCK(backing_object); 1626 break; 1627 } 1628 1629 if ( 1630 object->paging_in_progress != 0 || 1631 backing_object->paging_in_progress != 0 1632 ) { 1633 vm_object_qcollapse(object); 1634 VM_OBJECT_UNLOCK(backing_object); 1635 break; 1636 } 1637 /* 1638 * We know that we can either collapse the backing object (if 1639 * the parent is the only reference to it) or (perhaps) have 1640 * the parent bypass the object if the parent happens to shadow 1641 * all the resident pages in the entire backing object. 1642 * 1643 * This is ignoring pager-backed pages such as swap pages. 1644 * vm_object_backing_scan fails the shadowing test in this 1645 * case. 1646 */ 1647 if (backing_object->ref_count == 1) { 1648 /* 1649 * If there is exactly one reference to the backing 1650 * object, we can collapse it into the parent. 1651 */ 1652 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT); 1653 1654 /* 1655 * Move the pager from backing_object to object. 1656 */ 1657 if (backing_object->type == OBJT_SWAP) { 1658 /* 1659 * swap_pager_copy() can sleep, in which case 1660 * the backing_object's and object's locks are 1661 * released and reacquired. 1662 */ 1663 swap_pager_copy( 1664 backing_object, 1665 object, 1666 OFF_TO_IDX(object->backing_object_offset), TRUE); 1667 } 1668 /* 1669 * Object now shadows whatever backing_object did. 1670 * Note that the reference to 1671 * backing_object->backing_object moves from within 1672 * backing_object to within object. 1673 */ 1674 LIST_REMOVE(object, shadow_list); 1675 backing_object->shadow_count--; 1676 backing_object->generation++; 1677 if (backing_object->backing_object) { 1678 VM_OBJECT_LOCK(backing_object->backing_object); 1679 LIST_REMOVE(backing_object, shadow_list); 1680 LIST_INSERT_HEAD( 1681 &backing_object->backing_object->shadow_head, 1682 object, shadow_list); 1683 /* 1684 * The shadow_count has not changed. 1685 */ 1686 backing_object->backing_object->generation++; 1687 VM_OBJECT_UNLOCK(backing_object->backing_object); 1688 } 1689 object->backing_object = backing_object->backing_object; 1690 object->backing_object_offset += 1691 backing_object->backing_object_offset; 1692 1693 /* 1694 * Discard backing_object. 1695 * 1696 * Since the backing object has no pages, no pager left, 1697 * and no object references within it, all that is 1698 * necessary is to dispose of it. 1699 */ 1700 KASSERT(backing_object->ref_count == 1, ("backing_object %p was somehow re-referenced during collapse!", backing_object)); 1701 VM_OBJECT_UNLOCK(backing_object); 1702 1703 mtx_lock(&vm_object_list_mtx); 1704 TAILQ_REMOVE( 1705 &vm_object_list, 1706 backing_object, 1707 object_list 1708 ); 1709 mtx_unlock(&vm_object_list_mtx); 1710 1711 uma_zfree(obj_zone, backing_object); 1712 1713 object_collapses++; 1714 } else { 1715 vm_object_t new_backing_object; 1716 1717 /* 1718 * If we do not entirely shadow the backing object, 1719 * there is nothing we can do so we give up. 1720 */ 1721 if (object->resident_page_count != object->size && 1722 vm_object_backing_scan(object, 1723 OBSC_TEST_ALL_SHADOWED) == 0) { 1724 VM_OBJECT_UNLOCK(backing_object); 1725 break; 1726 } 1727 1728 /* 1729 * Make the parent shadow the next object in the 1730 * chain. Deallocating backing_object will not remove 1731 * it, since its reference count is at least 2. 1732 */ 1733 LIST_REMOVE(object, shadow_list); 1734 backing_object->shadow_count--; 1735 backing_object->generation++; 1736 1737 new_backing_object = backing_object->backing_object; 1738 if ((object->backing_object = new_backing_object) != NULL) { 1739 VM_OBJECT_LOCK(new_backing_object); 1740 LIST_INSERT_HEAD( 1741 &new_backing_object->shadow_head, 1742 object, 1743 shadow_list 1744 ); 1745 new_backing_object->shadow_count++; 1746 new_backing_object->generation++; 1747 vm_object_reference_locked(new_backing_object); 1748 VM_OBJECT_UNLOCK(new_backing_object); 1749 object->backing_object_offset += 1750 backing_object->backing_object_offset; 1751 } 1752 1753 /* 1754 * Drop the reference count on backing_object. Since 1755 * its ref_count was at least 2, it will not vanish. 1756 */ 1757 backing_object->ref_count--; 1758 VM_OBJECT_UNLOCK(backing_object); 1759 object_bypasses++; 1760 } 1761 1762 /* 1763 * Try again with this object's new backing object. 1764 */ 1765 } 1766 } 1767 1768 /* 1769 * vm_object_page_remove: 1770 * 1771 * Removes all physical pages in the given range from the 1772 * object's list of pages. If the range's end is zero, all 1773 * physical pages from the range's start to the end of the object 1774 * are deleted. 1775 * 1776 * The object must be locked. 1777 */ 1778 void 1779 vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 1780 boolean_t clean_only) 1781 { 1782 vm_page_t p, next; 1783 1784 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1785 if (object->resident_page_count == 0) 1786 return; 1787 1788 /* 1789 * Since physically-backed objects do not use managed pages, we can't 1790 * remove pages from the object (we must instead remove the page 1791 * references, and then destroy the object). 1792 */ 1793 KASSERT(object->type != OBJT_PHYS || object == kernel_object || 1794 object == kmem_object, 1795 ("attempt to remove pages from a physical object")); 1796 1797 vm_object_pip_add(object, 1); 1798 again: 1799 vm_page_lock_queues(); 1800 if ((p = TAILQ_FIRST(&object->memq)) != NULL) { 1801 if (p->pindex < start) { 1802 p = vm_page_splay(start, object->root); 1803 if ((object->root = p)->pindex < start) 1804 p = TAILQ_NEXT(p, listq); 1805 } 1806 } 1807 /* 1808 * Assert: the variable p is either (1) the page with the 1809 * least pindex greater than or equal to the parameter pindex 1810 * or (2) NULL. 1811 */ 1812 for (; 1813 p != NULL && (p->pindex < end || end == 0); 1814 p = next) { 1815 next = TAILQ_NEXT(p, listq); 1816 1817 if (p->wire_count != 0) { 1818 pmap_remove_all(p); 1819 if (!clean_only) 1820 p->valid = 0; 1821 continue; 1822 } 1823 if (vm_page_sleep_if_busy(p, TRUE, "vmopar")) 1824 goto again; 1825 if (clean_only && p->valid) { 1826 pmap_remove_write(p); 1827 if (p->valid & p->dirty) 1828 continue; 1829 } 1830 pmap_remove_all(p); 1831 vm_page_free(p); 1832 } 1833 vm_page_unlock_queues(); 1834 vm_object_pip_wakeup(object); 1835 } 1836 1837 /* 1838 * Routine: vm_object_coalesce 1839 * Function: Coalesces two objects backing up adjoining 1840 * regions of memory into a single object. 1841 * 1842 * returns TRUE if objects were combined. 1843 * 1844 * NOTE: Only works at the moment if the second object is NULL - 1845 * if it's not, which object do we lock first? 1846 * 1847 * Parameters: 1848 * prev_object First object to coalesce 1849 * prev_offset Offset into prev_object 1850 * prev_size Size of reference to prev_object 1851 * next_size Size of reference to the second object 1852 * 1853 * Conditions: 1854 * The object must *not* be locked. 1855 */ 1856 boolean_t 1857 vm_object_coalesce(vm_object_t prev_object, vm_ooffset_t prev_offset, 1858 vm_size_t prev_size, vm_size_t next_size) 1859 { 1860 vm_pindex_t next_pindex; 1861 1862 if (prev_object == NULL) 1863 return (TRUE); 1864 VM_OBJECT_LOCK(prev_object); 1865 if (prev_object->type != OBJT_DEFAULT && 1866 prev_object->type != OBJT_SWAP) { 1867 VM_OBJECT_UNLOCK(prev_object); 1868 return (FALSE); 1869 } 1870 1871 /* 1872 * Try to collapse the object first 1873 */ 1874 vm_object_collapse(prev_object); 1875 1876 /* 1877 * Can't coalesce if: . more than one reference . paged out . shadows 1878 * another object . has a copy elsewhere (any of which mean that the 1879 * pages not mapped to prev_entry may be in use anyway) 1880 */ 1881 if (prev_object->backing_object != NULL) { 1882 VM_OBJECT_UNLOCK(prev_object); 1883 return (FALSE); 1884 } 1885 1886 prev_size >>= PAGE_SHIFT; 1887 next_size >>= PAGE_SHIFT; 1888 next_pindex = OFF_TO_IDX(prev_offset) + prev_size; 1889 1890 if ((prev_object->ref_count > 1) && 1891 (prev_object->size != next_pindex)) { 1892 VM_OBJECT_UNLOCK(prev_object); 1893 return (FALSE); 1894 } 1895 1896 /* 1897 * Remove any pages that may still be in the object from a previous 1898 * deallocation. 1899 */ 1900 if (next_pindex < prev_object->size) { 1901 vm_object_page_remove(prev_object, 1902 next_pindex, 1903 next_pindex + next_size, FALSE); 1904 if (prev_object->type == OBJT_SWAP) 1905 swap_pager_freespace(prev_object, 1906 next_pindex, next_size); 1907 } 1908 1909 /* 1910 * Extend the object if necessary. 1911 */ 1912 if (next_pindex + next_size > prev_object->size) 1913 prev_object->size = next_pindex + next_size; 1914 1915 VM_OBJECT_UNLOCK(prev_object); 1916 return (TRUE); 1917 } 1918 1919 void 1920 vm_object_set_writeable_dirty(vm_object_t object) 1921 { 1922 struct vnode *vp; 1923 1924 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1925 if ((object->flags & OBJ_MIGHTBEDIRTY) != 0) 1926 return; 1927 vm_object_set_flag(object, OBJ_MIGHTBEDIRTY); 1928 if (object->type == OBJT_VNODE && 1929 (vp = (struct vnode *)object->handle) != NULL) { 1930 VI_LOCK(vp); 1931 vp->v_iflag |= VI_OBJDIRTY; 1932 VI_UNLOCK(vp); 1933 } 1934 } 1935 1936 #include "opt_ddb.h" 1937 #ifdef DDB 1938 #include <sys/kernel.h> 1939 1940 #include <sys/cons.h> 1941 1942 #include <ddb/ddb.h> 1943 1944 static int 1945 _vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry) 1946 { 1947 vm_map_t tmpm; 1948 vm_map_entry_t tmpe; 1949 vm_object_t obj; 1950 int entcount; 1951 1952 if (map == 0) 1953 return 0; 1954 1955 if (entry == 0) { 1956 tmpe = map->header.next; 1957 entcount = map->nentries; 1958 while (entcount-- && (tmpe != &map->header)) { 1959 if (_vm_object_in_map(map, object, tmpe)) { 1960 return 1; 1961 } 1962 tmpe = tmpe->next; 1963 } 1964 } else if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { 1965 tmpm = entry->object.sub_map; 1966 tmpe = tmpm->header.next; 1967 entcount = tmpm->nentries; 1968 while (entcount-- && tmpe != &tmpm->header) { 1969 if (_vm_object_in_map(tmpm, object, tmpe)) { 1970 return 1; 1971 } 1972 tmpe = tmpe->next; 1973 } 1974 } else if ((obj = entry->object.vm_object) != NULL) { 1975 for (; obj; obj = obj->backing_object) 1976 if (obj == object) { 1977 return 1; 1978 } 1979 } 1980 return 0; 1981 } 1982 1983 static int 1984 vm_object_in_map(vm_object_t object) 1985 { 1986 struct proc *p; 1987 1988 /* sx_slock(&allproc_lock); */ 1989 FOREACH_PROC_IN_SYSTEM(p) { 1990 if (!p->p_vmspace /* || (p->p_flag & (P_SYSTEM|P_WEXIT)) */) 1991 continue; 1992 if (_vm_object_in_map(&p->p_vmspace->vm_map, object, 0)) { 1993 /* sx_sunlock(&allproc_lock); */ 1994 return 1; 1995 } 1996 } 1997 /* sx_sunlock(&allproc_lock); */ 1998 if (_vm_object_in_map(kernel_map, object, 0)) 1999 return 1; 2000 if (_vm_object_in_map(kmem_map, object, 0)) 2001 return 1; 2002 if (_vm_object_in_map(pager_map, object, 0)) 2003 return 1; 2004 if (_vm_object_in_map(buffer_map, object, 0)) 2005 return 1; 2006 return 0; 2007 } 2008 2009 DB_SHOW_COMMAND(vmochk, vm_object_check) 2010 { 2011 vm_object_t object; 2012 2013 /* 2014 * make sure that internal objs are in a map somewhere 2015 * and none have zero ref counts. 2016 */ 2017 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2018 if (object->handle == NULL && 2019 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2020 if (object->ref_count == 0) { 2021 db_printf("vmochk: internal obj has zero ref count: %ld\n", 2022 (long)object->size); 2023 } 2024 if (!vm_object_in_map(object)) { 2025 db_printf( 2026 "vmochk: internal obj is not in a map: " 2027 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n", 2028 object->ref_count, (u_long)object->size, 2029 (u_long)object->size, 2030 (void *)object->backing_object); 2031 } 2032 } 2033 } 2034 } 2035 2036 /* 2037 * vm_object_print: [ debug ] 2038 */ 2039 DB_SHOW_COMMAND(object, vm_object_print_static) 2040 { 2041 /* XXX convert args. */ 2042 vm_object_t object = (vm_object_t)addr; 2043 boolean_t full = have_addr; 2044 2045 vm_page_t p; 2046 2047 /* XXX count is an (unused) arg. Avoid shadowing it. */ 2048 #define count was_count 2049 2050 int count; 2051 2052 if (object == NULL) 2053 return; 2054 2055 db_iprintf( 2056 "Object %p: type=%d, size=0x%jx, res=%d, ref=%d, flags=0x%x\n", 2057 object, (int)object->type, (uintmax_t)object->size, 2058 object->resident_page_count, object->ref_count, object->flags); 2059 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%jx\n", 2060 object->shadow_count, 2061 object->backing_object ? object->backing_object->ref_count : 0, 2062 object->backing_object, (uintmax_t)object->backing_object_offset); 2063 2064 if (!full) 2065 return; 2066 2067 db_indent += 2; 2068 count = 0; 2069 TAILQ_FOREACH(p, &object->memq, listq) { 2070 if (count == 0) 2071 db_iprintf("memory:="); 2072 else if (count == 6) { 2073 db_printf("\n"); 2074 db_iprintf(" ..."); 2075 count = 0; 2076 } else 2077 db_printf(","); 2078 count++; 2079 2080 db_printf("(off=0x%jx,page=0x%jx)", 2081 (uintmax_t)p->pindex, (uintmax_t)VM_PAGE_TO_PHYS(p)); 2082 } 2083 if (count != 0) 2084 db_printf("\n"); 2085 db_indent -= 2; 2086 } 2087 2088 /* XXX. */ 2089 #undef count 2090 2091 /* XXX need this non-static entry for calling from vm_map_print. */ 2092 void 2093 vm_object_print( 2094 /* db_expr_t */ long addr, 2095 boolean_t have_addr, 2096 /* db_expr_t */ long count, 2097 char *modif) 2098 { 2099 vm_object_print_static(addr, have_addr, count, modif); 2100 } 2101 2102 DB_SHOW_COMMAND(vmopag, vm_object_print_pages) 2103 { 2104 vm_object_t object; 2105 int nl = 0; 2106 int c; 2107 2108 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2109 vm_pindex_t idx, fidx; 2110 vm_pindex_t osize; 2111 vm_paddr_t pa = -1; 2112 int rcount; 2113 vm_page_t m; 2114 2115 db_printf("new object: %p\n", (void *)object); 2116 if (nl > 18) { 2117 c = cngetc(); 2118 if (c != ' ') 2119 return; 2120 nl = 0; 2121 } 2122 nl++; 2123 rcount = 0; 2124 fidx = 0; 2125 osize = object->size; 2126 if (osize > 128) 2127 osize = 128; 2128 for (idx = 0; idx < osize; idx++) { 2129 m = vm_page_lookup(object, idx); 2130 if (m == NULL) { 2131 if (rcount) { 2132 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2133 (long)fidx, rcount, (long)pa); 2134 if (nl > 18) { 2135 c = cngetc(); 2136 if (c != ' ') 2137 return; 2138 nl = 0; 2139 } 2140 nl++; 2141 rcount = 0; 2142 } 2143 continue; 2144 } 2145 2146 2147 if (rcount && 2148 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) { 2149 ++rcount; 2150 continue; 2151 } 2152 if (rcount) { 2153 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2154 (long)fidx, rcount, (long)pa); 2155 if (nl > 18) { 2156 c = cngetc(); 2157 if (c != ' ') 2158 return; 2159 nl = 0; 2160 } 2161 nl++; 2162 } 2163 fidx = idx; 2164 pa = VM_PAGE_TO_PHYS(m); 2165 rcount = 1; 2166 } 2167 if (rcount) { 2168 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2169 (long)fidx, rcount, (long)pa); 2170 if (nl > 18) { 2171 c = cngetc(); 2172 if (c != ' ') 2173 return; 2174 nl = 0; 2175 } 2176 nl++; 2177 } 2178 } 2179 } 2180 #endif /* DDB */ 2181